JP5223207B2 - Photosensitive resin composition, resist pattern forming method using the same, and printed wiring board manufacturing method - Google Patents

Description

  The present invention relates to a photosensitive resin composition, a method for forming a resist pattern using the same, and a method for producing a printed wiring board.

  Conventionally, solder resist has been used in the production of printed wiring boards, but in recent years it has also been used in new LSI packages such as BGA (ball grid array), PGA (pin grid array), and CSP (chip size package). It has become like this. The solder resist is an indispensable material as a protective film or a permanent mask that prevents the solder from adhering to unnecessary portions in the soldering process.

  As a method for forming a solder resist, for example, there is a method of printing a thermosetting resin composition by a screen printing method. However, in recent years, with the increase in wiring density, the screen printing method has a limit in terms of resolution, and a photo solder resist that forms a pattern by a photographic method has been actively used. In particular, an alkali-developable photosensitive resin composition (photo-curable resin composition) that can be developed with a weak alkaline solution such as a sodium carbonate solution has become mainstream from the viewpoint of working environment conservation, global environment conservation, and the like ( For example, see Patent Documents 1 and 2 below).

  However, a solder resist formed using an alkali development type photosensitive resin composition has a problem that it is still insufficient in terms of durability. That is, chemical resistance, water resistance, heat resistance and the like tend to be inferior to a solder resist formed using a conventional thermosetting resin composition or a solvent development type photosensitive resin composition. The alkali-developable photosensitive resin composition is mainly composed of a resin having a hydrophilic group so that alkali development is possible. Therefore, the formed solder resist is infiltrated with chemicals, water, water vapor, and the like. Cheap. As a result, it is considered that the adhesion between the resist film and copper is lowered. In particular, in semiconductor packages such as BGA and CSP, the solder resist is particularly required to have resistance to PCT (pressure cooker resistance) and electric corrosion resistance, which is also referred to as heat and moisture resistance, but sufficient performance has not yet been obtained. is the current situation.

  Furthermore, since the mounting method changes from insertion mounting to surface mounting, the temperature applied to the package during mounting tends to increase. Specifically, in the case of surface mounting, cream solder is printed in advance on necessary parts, the whole is heated with infrared rays, and the solder is reflowed and fixed, so that the temperature reached inside and outside of the package is remarkably high at 220 to 280 ° C. . Therefore, in the solder resist formed using the conventional liquid photosensitive resin composition, there is a problem that a crack occurs due to thermal shock or the substrate and the sealing material are peeled off, and the improvement is required. Yes. In addition, thermal reliability is applied to the reliability of connection with semiconductor elements (for example, thermal history is added with -55 ° C for 30 minutes and 125 ° C for 30 minutes as one cycle, and cracks occur in the coating after 1000 cycles. Do not do). That is, the photosensitive resin composition used for manufacturing a semiconductor package is usually provided on a wiring board for mounting a semiconductor chip, and then sealed with a sealing material, and therefore thermal shock is applied. Therefore, there is also a demand for a characteristic that the substrate for mounting the semiconductor chip, the semiconductor chip and the sealing material for sealing the substrate are not peeled off and cracks are not generated. Moreover, improvement of the photosensitive resin composition is also considered from the point of the required characteristic to the material which follows the increase in pin count and signal speed-up (for example, refer nonpatent literature 1 and 2 below).

JP-A 61-243869 JP-A-1-141904 Kasuga Ikuo, "Ultra-small package CSP / BGA technology", Nikkan Kogyo Shimbun, 1998 Yoshiyuki Tsuru et al., "Journal of Circuit Packaging Society", 10, (2) 101-107, 1995

  However, in the conventional photosensitive resin composition, the exposure latitude (small aperture size and image variation rate due to different exposure conditions) and development latitude (open size and image variation rate due to different development conditions are small) ), High-performance cured film (solder resist) excellent in PCT resistance (moisture and heat resistance), via shape, heat resistance, developability, adhesion, thermal shock resistance, electrical corrosion resistance, flexibility, and mechanical properties It was difficult.

  The present invention has been made in view of the above-mentioned problems of the prior art, exposure latitude, development latitude, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, Photosensitive resin composition suitable for manufacturing printed wiring boards, high-density multilayer boards, semiconductor packages, and the like, and a resist using the same, capable of obtaining a high-performance cured film excellent in flexibility and mechanical properties It aims at providing the formation method of a pattern, and the manufacturing method of a printed wiring board.

In order to achieve the above object, the present invention provides (A) (a) an ester compound of an epoxy compound having two or more epoxy groups in one molecule and (b) an unsaturated monocarboxylic acid, and (c) a saturated product. Or an acid-modified vinyl group-containing epoxy resin that is an addition reaction product obtained by adding an unsaturated polybasic acid anhydride, (B) a photopolymerization initiator, (C) a diluent, (D) a curing agent, E) an acrylic resin having a weight average molecular weight of 30,000 to 120,000, and (a) any one or more of compounds represented by general formula (2) or (3 ) described later with an epoxy compound A photosensitive resin composition is provided.

  According to such a photosensitive resin composition, by having the above-described configuration, exposure tolerance, development tolerance, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, flexible High-performance cured film having excellent properties and mechanical properties can be obtained. Therefore, the said photosensitive resin composition can be used suitably for manufacture of a printed wiring board etc.

［式中、Ｒ^１は水素原子又はグリシジル基を示し、Ｒ^２は水素原子又はメチル基を示し、ｎ１は１以上の整数を示す。なお、複数存在するＲ^１及びＲ^２のそれぞれは同一でも異なっていてもよい。］

［式中、Ｒ^３は水素原子又はグリシジル基を示し、Ｒ^４は水素原子又はメチル基を示し、ｎ２は１以上の整数を示す。なお、複数存在するＲ^３及びＲ^４のそれぞれは同一でも異なっていてもよい。］

［式中、Ｒ^５は水素原子又はメチル基を示し、ｎ３は１以上の整数を示す。なお、複数存在するＲ^５は同一でも異なっていてもよい。］

［式中、Ｒ^６は水素原子又はメチル基を示し、ｎ４は１以上の整数を示す。なお、複数存在するＲ^６は同一でも異なっていてもよい。］ In the photosensitive resin composition of the present invention, since the electric characteristics of the resulting cured film can be further improved, the (a) epoxy compound is represented by the following general formula (1), (2), (3) or (4). Any one or more of the compounds represented is preferable.

[Wherein, R ¹ represents a hydrogen atom or a glycidyl group, R ² represents a hydrogen atom or a methyl group, and n1 represents an integer of 1 or more. A plurality of R ¹ and R ² may be the same or different. ]

[Wherein, R ³ represents a hydrogen atom or a glycidyl group, R ⁴ represents a hydrogen atom or a methyl group, and n2 represents an integer of 1 or more. A plurality of R ³ and R ⁴ may be the same or different. ]

[Wherein, R ⁵ represents a hydrogen atom or a methyl group, and n3 represents an integer of 1 or more. A plurality of R ⁵ may be the same or different. ]

[Wherein, R ⁶ represents a hydrogen atom or a methyl group, and n4 represents an integer of 1 or more. A plurality of R ⁶ may be the same or different. ]

  Moreover, it is preferable that the photosensitive resin composition of this invention further contains (F) elastomer. When the photosensitive resin composition contains the elastomer (F), the thermal shock resistance of the obtained cured film can be further improved.

  Moreover, it is preferable that the photosensitive resin composition of this invention further contains (G) phenoxy resin. When the photosensitive resin composition contains the (G) phenoxy resin, the heat resistance of the obtained cured film can be further improved.

  Furthermore, it is preferable that the photosensitive resin composition of the present invention further contains (H) a blocked isocyanate. When the photosensitive resin composition contains (H) blocked isocyanate, the heat resistance of the obtained cured film can be further improved.

  The present invention also includes a step of laminating a photosensitive resin composition layer comprising the photosensitive resin composition of the present invention on a substrate, and irradiating the photosensitive resin composition layer with an actinic ray in an image form to illuminate an exposed portion. There is provided a method for forming a resist pattern, which is cured, and then an unexposed portion is removed by development.

  The present invention further provides a method for producing a printed wiring board, wherein a permanent mask is formed on a substrate by the method for forming a resist pattern of the present invention.

  According to the method for forming a resist pattern and the method for producing a printed wiring board, since the photosensitive resin composition of the present invention is used, exposure latitude, development tolerance, PCT resistance, via shape, heat resistance Further, it is possible to efficiently form a cured film such as a permanent mask (solder resist) excellent in developability, adhesion, thermal shock resistance, electric corrosion resistance, flexibility, and mechanical properties.

  According to the present invention, high-performance curing excellent in exposure tolerance, development tolerance, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, flexibility, and mechanical properties. A photosensitive resin composition that can form a film and is suitably used for the production of printed wiring boards and semiconductor packages, a resist pattern forming method using the same, and a printed wiring board manufacturing method can be provided. .

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof. In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding thereto, (meth) acrylate means acrylate and corresponding methacrylate, (meth) acryloyl group means acryloyl group and The corresponding methacryloyl group is meant.

(Photosensitive resin composition)
The photosensitive resin composition of the present invention comprises (A) (a) an epoxy compound having two or more epoxy groups in one molecule (hereinafter sometimes referred to as “component (a)”) and (b) an unsaturated monocarboxylic acid. An addition of (c) a saturated or unsaturated polybasic acid anhydride (hereinafter sometimes referred to as “component (c)”) to an esterified product with an acid (hereinafter sometimes referred to as “component (b)”) An acid-modified vinyl group-containing epoxy resin (hereinafter sometimes referred to as “component (A)”) as a reaction product, (B) a photopolymerization initiator (hereinafter sometimes referred to as “component (B)”), ( C) diluent (hereinafter sometimes referred to as “component (C)”), (D) curing agent (hereinafter sometimes referred to as “component (D)”), and (E) weight average molecular weight of 30,000 to 120,000 acrylic resin (hereinafter referred to as “(E) And "called), it is those which contain.

  (A) As an epoxy compound (epoxy resin) having two or more epoxy groups in one molecule, for example, phenol novolac type epoxy resin, cresol novolac type epoxy resin, salicylaldehyde type epoxy resin, bisphenol A type epoxy resin, bisphenol Examples thereof include F-type epoxy resins, bisphenol A-type phenol novolac-type epoxy resins, and bisphenol F-type phenol novolac-type epoxy resins.

  Among these, as the epoxy compound (a), epoxy resins represented by the above general formulas (1) to (4) are preferable from the viewpoint of exposure latitude and development latitude, and in particular, the general formula (1). The bisphenol A type phenol novolac type epoxy resin mentioned above is preferable.

  Although there is no restriction | limiting in the manufacturing method of the epoxy resin represented by the said General formula (1), It can obtain by making epichlorohydrin react with a phenol novolak-type resin and a bisphenol F-type resin by a well-known method. Examples of the bisphenol F type phenol novolac type epoxy resin represented by the general formula (1) include YDPF series manufactured by Toto Kasei Co., Ltd.

  (B) As unsaturated monocarboxylic acid (unsaturated group-containing monocarboxylic acid), for example, acrylic acid, dimer of acrylic acid, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid , Crotonic acid, α-cyanocinnamic acid, half-ester compound which is a reaction product of hydroxyl group-containing acrylate and saturated or unsaturated dibasic acid anhydride, unsaturated group-containing monoglycidyl ether and saturated or unsaturated dibasic acid anhydride And half-ester compounds which are reaction products with products. These half ester compounds are obtained by reacting a hydroxyl group-containing acrylate or unsaturated group-containing monoglycidyl ether with a saturated or unsaturated dibasic acid anhydride in an equimolar ratio. These (b) unsaturated group containing monocarboxylic acids can be used individually by 1 type or in combination of 2 or more types.

  (B) Examples of the hydroxyl group-containing acrylate and unsaturated group-containing monoglycidyl ether used in the synthesis of the half ester compound as an example of the unsaturated group-containing monocarboxylic acid include hydroxyethyl acrylate, hydroxyethyl methacrylate, and hydroxypropyl acrylate. , Hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol pentaacrylate , Pentaerythritol pentamethacrylate , Glycidyl acrylate and glycidyl methacrylate and the like.

  Examples of the saturated or unsaturated dibasic acid anhydride used for the synthesis of the half ester compound include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydro Examples thereof include phthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride and the like.

  In the reaction of (a) the epoxy compound and (b) the unsaturated group-containing monocarboxylic acid in the present invention, (b) the unsaturated group-containing monocarboxylic acid is 0 with respect to 1 equivalent of the epoxy group of the epoxy compound. It is preferable to react at a ratio of 0.6 to 1.10 equivalent, more preferably at a ratio of 0.75 to 1.05 equivalent, and at a ratio of 0.9 to 1.0 equivalent. It is particularly preferred.

  The (a) epoxy compound and (b) the unsaturated group-containing monocarboxylic acid can be dissolved and reacted in an organic solvent. Examples of the organic solvent include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate, aliphatic carbonization such as octane and decane Examples thereof include petroleum solvents such as hydrogen, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

  Furthermore, it is preferable to use a catalyst in order to promote the reaction between the component (a) and the component (b). Examples of the catalyst used include triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, and triphenylphosphine. It is preferable that the usage-amount of a catalyst is 0.1-10 mass parts with respect to a total of 100 mass parts of (a) component and (b) component.

  Moreover, it is preferable to use a polymerization inhibitor for the purpose of preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol and the like. It is preferable that the usage-amount of a polymerization inhibitor is 0.01-1 mass part with respect to a total of 100 mass parts of (a) component and (b) component.

  Moreover, it is preferable that the reaction temperature at the time of making (a) component and (b) component react is 60-150 degreeC, and it is more preferable that it is 80-120 degreeC.

  Furthermore, (b) unsaturated group-containing monocarboxylic acid, if necessary, polybasic acid anhydrides such as trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, biphenyl tetracarboxylic anhydride, It can be used in combination with monocarboxylic acid compounds such as phenylglycine and hydroxyacetic acid, and phenolic compounds such as p-hydroxyphenethyl alcohol.

  In the present invention, the (A) acid-modified vinyl group-containing epoxy resin can be obtained by reacting the component (c) with the reaction product (A ′) of the component (a) and the component (b).

  (C) As saturated or unsaturated polybasic acid anhydride (saturated or unsaturated polybasic acid anhydride), for example, succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride Ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride and the like.

  In the reaction between the reaction product (A ′) of the component (a) and the component (b) and the component (c), the component (c) is added to 1 equivalent of the hydroxyl group in the reaction product (A ′). By making 0.1-1.0 equivalent reaction, the acid value of the (A) acid-modified vinyl group containing epoxy resin obtained can be adjusted.

  In addition, it is preferable that the acid value of (A) acid-modified vinyl group containing epoxy resin is 30-150 mgKOH / g, and it is more preferable that it is 50-120 mgKOH / g. If the acid value is less than 30 mg KOH / g, the solubility of the photosensitive resin composition in a dilute alkali solution tends to be reduced, and if it exceeds 150 mg KOH / g, the electric properties of the cured film tend to be reduced. The reaction temperature between the reaction product (A ′) and the component (c) is preferably 60 to 120 ° C.

  If necessary, as the epoxy resin (a), for example, a cresol novolac type epoxy resin, a bisphenol A type epoxy resin, or a hydrogenated bisphenol A type epoxy resin can be partially used together. Further, (A) acid-modified vinyl group-containing epoxy resin, styrene-maleic anhydride copolymer modified with hydroxyethyl acrylate or styrene-maleic anhydride copolymer modified with styrene-maleic anhydride A part of the acid resin may be used in combination.

  In the photosensitive resin composition, the content of the component (A) is preferably 40 to 80% by mass, based on the total solid content of the component (A) and the component (E), and is preferably 45 to 75% by mass. More preferably, it is particularly preferably 50 to 70% by mass. When this content is less than 40% by mass, the exposure tolerance tends to be inferior, and when it exceeds 80% by mass, the development tolerance tends to be inferior.

  Examples of the (B) photopolymerization initiator used in the present invention include benzoins such as benzoin, benzoin methyl ether, and benzoin isopropyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 2,2-diethoxy. 2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,2-di Acetophenones such as ethoxyacetophenone and N, N-dimethylaminoacetophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquino Anthraquinones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, thioxanthones such as 2,4-diisopropylthioxanthone, ketones such as acetophenone dimethyl ketal and benzyl dimethyl ketal, benzophenone, methyl Benzophenones such as benzophenone, 4,4′-dichlorobenzophenone, 4,4′-bis (diethylamino) benzophenone, Michler's ketone, 4-benzoyl-4′-methyldiphenyl sulfide, 2- (o-chlorophenyl) -4,5- Diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) 2,4,5-triarylimidazole dimer such as -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1 , 7-bis (9,9′-acridinyl) heptane and the like, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. These are used singly or in combination of two or more.

  Further, (B) photopolymerization initiation assistants include N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, dimethylethanolamine, triethylamine, There may be mentioned tertiary amines such as ethanolamine. These are used individually by 1 type or in combination of 2 or more types.

  In the photosensitive resin composition, the content of the (B) photopolymerization initiator is preferably 0.5 to 20% by mass, and 1 to 15% by mass based on the total solid content of the photosensitive resin composition. It is more preferable that it is 2-10 mass%. If this content is less than 0.5% by mass, the photosensitivity tends to decrease and the exposed area tends to be eluted during development, and if it exceeds 20% by mass, the heat resistance of the cured film tends to decrease.

  As the diluent (C) used in the present invention, for example, an organic solvent and / or a photopolymerizable monomer can be used. Examples of the organic solvent include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate, aliphatic carbonization such as octane and decane Examples thereof include petroleum solvents such as hydrogen, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

  The photopolymerizable monomer can be used for the purpose of improving photosensitivity and various characteristics. Examples of such photopolymerizable monomers include 2-hydroxyethyl (meth) acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and N, N-dimethyl. (Meth) acrylate, N-methylol (meth) acrylamide, polyethylene glycol, polypropylene glycol, polyethylene glycol or propylene glycol of bisphenol A, mono- or polyfunctional (meth) acrylates of tris (2-hydroxyethyl) isocyanuric acid, triglycidyl Photopolymerizable monomers such as (meth) acrylates of glycidyl ether such as isocyanurate and diallyl phthalate can be used. These can be used individually by 1 type or in mixture of 2 or more types.

  (C) When using a photopolymerizable monomer as a diluent, the content thereof is 0.5 to 30 parts by mass with respect to 100 parts by mass of the total solid content of the component (A) and the component (E). Preferably, it is 5-25 mass parts, More preferably, it is 10-20 mass parts. If this content is less than 0.5 parts by mass, the photosensitivity tends to be low and the exposed part tends to be eluted during development, and if it exceeds 30 parts by mass, the heat resistance of the cured film tends to be reduced.

  As the (D) curing agent used in the present invention, (A) an acid-modified vinyl group-containing epoxy resin that is a compound that itself cures with heat, ultraviolet light, or the like, or a photocurable resin component in a photosensitive resin composition A compound that cures by reacting with a carboxyl group or a hydroxyl group with heat or ultraviolet rays is preferred. By using this (D) curing agent, the heat resistance, adhesion, chemical resistance, etc. of the finally obtained cured film can be improved.

  (D) As a hardening | curing agent, an epoxy compound, a melamine compound, a urea compound, an oxazoline compound etc. can be mentioned as a thermosetting compound, for example. Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol S type epoxy resin, and biphenyl type epoxy resin. Or heterocyclic epoxy resins such as triglycidyl isocyanurate, and bixylenol type epoxy resins. Examples of the melamine compound include triaminotriazine, hexamethoxymelamine, hexabutoxylated melamine and the like. Examples of the urea compound include dimethylol urea. These (D) curing agents are used singly or in combination of two or more.

  In the photosensitive resin composition, the content of the (D) curing agent is preferably 2 to 60 parts by mass with respect to 100 parts by mass of the total solid content of the component (A) and the component (E). More preferably, it is 55 mass parts, and it is especially preferable that it is 20-50 mass parts. If this content is less than 2 parts by mass, the heat resistance of the resulting cured film tends to be reduced, and if it exceeds 60 parts by mass, the developability tends to be reduced.

  The photosensitive resin composition of the present invention preferably contains an epoxy resin curing agent for the purpose of further improving various properties such as heat resistance, adhesion and chemical resistance of the cured film.

  Specific examples of such an epoxy resin curing agent include, for example, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methyl. Imidazole derivatives such as -5-hydroxymethylimidazole; guanamines such as acetoguanamine and benzoguanamine; diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, polybasic hydrazide, etc. These organic acid salts and / or epoxy adducts; amine complexes of boron trifluoride; ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-xylyl- S Triazine derivatives such as triazine; trimethylamine, triethanolamine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4,6-tris ( Tertiary amines such as dimethylaminophenol), tetramethylguanidine, m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac, alkylphenol novolac; tributylphosphine, triphenylphosphine, tris-2-cyanoethyl Organic phosphines such as phosphine; phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosnium chloride Quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; the above polybasic acid anhydrides; diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenylthiopyrylium Examples include hexafluorophosphate.

  These epoxy resin curing agents are used singly or in combination of two or more. When using an epoxy resin hardening | curing agent, it is preferable that the content is 0.01-20 mass parts with respect to 100 mass parts of solid content total of (A) component and (E) component, More preferably, it is 10 mass parts, and it is especially preferable that it is 0.5-5 mass parts.

  Moreover, a part of said epoxy resin hardening | curing agent can be substituted to another epoxy resin hardening | curing agent. Examples of the other epoxy resin curing agent include (a) an epoxy compound which is a starting material for (A) an acid-modified vinyl group-containing epoxy resin. Specific examples include novolak-type epoxy resins, bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, salicylaldehyde-type epoxy resins, epoxy group-containing polyamide resins, and epoxy group-containing polyamideimide resins. Moreover, the epoxy resin represented by the said General Formula (1)-(4) can also be used as another epoxy resin hardening | curing agent. In addition, for example, biphenyl type epoxy resins such as YX4000 manufactured by Yuka Shell Epoxy Co., Ltd., dicyclo type epoxy resins such as Epicron HP7200 manufactured by Dainippon Ink and Chemicals, Ltd., manufactured by Dainippon Ink and Chemicals, Inc. Glycidyl amine type epoxy resins such as Epicron 430 and Sumitomo Chemical Co., Ltd. ELM100, 120, 434, etc., glycidyl ester type epoxy resins such as Denacol EX-721 manufactured by Nagase Chemical Industries, Ltd., Dainippon Ink and Chemicals, Inc. Naphthalene type epoxy resin such as Epiklon HP-4032 manufactured by Co., Ltd., heterocyclic type epoxy resin such as Tris (2,3-epoxypropyl) isocyanurate (Nissan Chemical Industry Co., Ltd.), manufactured by Toto Kasei Co., Ltd. Modified bisfees such as EBPS-300 and EXA-4004 manufactured by Dainippon Ink & Chemicals, Inc. Such Lumpur S type epoxy resins. These can be used individually by 1 type or in combination of 2 or more types.

  In the present invention, when these epoxy resin curing agents are used, the content thereof is preferably 1 to 50% by mass, and 5 to 30% by mass based on the total solid content of the photosensitive resin composition. Is more preferable. When this content is less than 1% by mass, curing tends to be insufficient, and when it exceeds 50% by mass, problems tend to occur in photosensitive characteristics.

  The acrylic resin as component (E) has a weight average molecular weight of 30,000 to 120,000, preferably 35,000 to 100,000, and more preferably 40,000 to 80,000. . When the weight average molecular weight is in the range of 30,000 to 120,000, a resist having excellent exposure tolerance and development tolerance can be obtained. Here, the weight average molecular weight is measured by gel permeation chromatography, and a value converted to standard polystyrene is used.

  The (E) acrylic resin can be produced, for example, by radical polymerization of a polymerizable monomer. Examples of the polymerizable monomer include (meth) acrylic acid, (meth) acrylic acid alkyl ester, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid dimethylaminoethyl ester, and (meth) acrylic acid diethylaminoethyl. Ester, (meth) acrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, (meth) acrylic acid, α-bromo ( Examples include meth) acrylic acid, α-chloro (meth) acrylic acid, β-furyl (meth) acrylic acid, β-styryl (meth) acrylic acid and the like. These can be used individually by 1 type or in combination of 2 or more types.

  Examples of the (meth) acrylic acid alkyl ester include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, (meth ) Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, and structural isomers thereof. These can be used individually by 1 type or in combination of 2 or more types.

  Further, (E) the acrylic resin may be a copolymer of the polymerizable monomer and another copolymerizable monomer. The copolymerizable monomer is not particularly limited as long as it can be copolymerized with the polymerizable monomer, and can be polymerized, for example, styrene, vinyltoluene, α-methylstyrene, p-methylstyrene, p-ethylstyrene, and the like. Styrene derivatives, esters of vinyl alcohol such as acrylamide, acrylonitrile, vinyl-n-butyl ether, maleic acid monoester such as maleic acid, maleic anhydride, monomethyl maleate, monoethyl maleate, monoisopropyl maleate, fumaric acid, Cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid and the like can be mentioned. These can be used individually by 1 type or in combination of 2 or more types.

  The (E) acrylic resin preferably contains a carboxyl group from the viewpoint of alkali developability. The (E) acrylic resin having a carboxyl group can be produced, for example, by radical polymerization of a polymerizable monomer having a carboxyl group and another polymerizable monomer. As the polymerizable monomer having a carboxyl group, methacrylic acid is preferable.

  The (E) acrylic resin preferably contains (meth) acrylic acid alkyl ester and (meth) acrylic acid as monomer units from the viewpoint of exposure latitude and development latitude.

  The (E) acrylic resin preferably contains styrene and / or a styrene derivative as a monomer unit from the viewpoint of adhesion and chemical resistance (solder heat resistance).

  In order to obtain an (E) acrylic resin having good adhesion and chemical resistance (solder heat resistance) using the styrene and / or styrene derivative as a monomer, the styrene and / or styrene derivative based on the total amount of the monomer is used. The content is preferably 3 to 30% by mass, more preferably 4 to 28% by mass, and particularly preferably 5 to 27% by mass. If this content is less than 3% by mass, the adhesion tends to be inferior, and if it exceeds 30% by mass, the developability tends to deteriorate.

  The acid value of the (E) acrylic resin is preferably 30 to 200 mgKOH / g, more preferably 80 to 190 mgKOH / g, and particularly preferably 100 to 180 mgKOH / g. When the acid value is less than 30 mgKOH / g, the development time tends to be long, and when it exceeds 200 mgKOH / g, the developer resistance of the photocured resist tends to be lowered. Moreover, when performing solvent development at the time of image development, it is preferable to prepare the polymerizable monomer which has a carboxyl group in a small quantity. Moreover, the said (E) acrylic resin may have a photosensitive group as needed.

Here, the acid value of the said (A) component or (E) component can be measured with the following method. First, after precisely weighing about 1 g of the component (A) or component (E) in the present invention, 30 g of acetone is added to uniformly dissolve the component (A) or component (E). Next, an appropriate amount of phenolphthalein as an indicator is added to the solution, and titration is performed using a 0.1N aqueous KOH solution. And from the titration result, the following formula (1);
A = 10 × Vf × 56.1 / (Wp × I) (1)
To calculate the acid value. In the formula, A represents the acid value (mgKOH / g), Vf represents the titration amount (mL) of phenolphthalein, Wp represents the weight (g) of the component (A) or the component (E), I shows the ratio (mass%) of the non volatile matter of (A) component or (E) component.

  These (E) acrylic resins can be used singly or in combination of two or more. As an acrylic resin in the case of using two or more types in combination, for example, two or more types of acrylic resins comprising different copolymerization components, two or more types of acrylic resins having different weight average molecular weights, and two or more types of acrylic resins having different degrees of dispersion are used. An acrylic resin etc. are mentioned. In addition, a polymer having a multimode molecular weight distribution described in JP-A No. 11-327137 can also be used. Moreover, (E) When using 2 or more components of an acrylic resin, the acrylic resin with the largest blending amount may have a weight average molecular weight of 30,000 to 120,000.

  Furthermore, the (E) acrylic resin in the present invention is preferably soluble in the organic solvent at 25 ° C. from the viewpoint of exposure latitude and development tolerance.

  In the photosensitive resin composition, the content of the (E) acrylic resin is preferably 20 to 60% by mass based on the total solid content of the (A) component and the (E) component, and is preferably 25 to 55% by mass. It is more preferable that it is, and it is especially preferable that it is 30-50 mass%. When the content is less than 20% by mass, the development tolerance tends to be inferior, and when it exceeds 60% by mass, the exposure tolerance tends to be inferior.

  It is preferable that the photosensitive resin composition of the present invention further contains (F) an elastomer. (F) By containing an elastomer, the adhesiveness with the conductor layer of the printed wiring board when the photosensitive resin composition is used for the solder resist can be further improved, and the heat resistance and thermal shock of the cured film are improved. , Flexibility and toughness can be further improved.

  Examples of (F) elastomers include styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, acrylic elastomers, and silicone elastomers. These (F) elastomers are composed of a hard segment component and a soft segment component. In general, the former contributes to heat resistance and strength, and the latter contributes to flexibility and toughness.

  Examples of the styrenic elastomer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and the like. As a component constituting the styrene-based elastomer, styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene can be used in addition to styrene. Specifically, Tufprene, Solprene T, Asaprene T, Tuftec (Asahi Kasei Kogyo Co., Ltd.), Elastomer AR (Aron Kasei Co., Ltd.), Clayton G, Super Reflex (October, Shell Japan Co., Ltd.), JSR- TR, TSR-SIS, Dynalon (manufactured by Nippon Synthetic Rubber Co., Ltd.), Denka STR (manufactured by Denki Kagaku Co., Ltd.), Quintac (manufactured by Nippon Zeon Co., Ltd.), TPE-SB series (manufactured by Sumitomo Chemical Co., Ltd.), Examples include Lavalon (manufactured by Mitsubishi Chemical Corporation), Septon, Hybler (manufactured by Kuraray Co., Ltd.), Sumiflex (manufactured by Sumitomo Bakelite Co., Ltd.), Rheostomer, Actimer (manufactured by Riken Vinyl Industry Co., Ltd.)

  The olefin elastomer is a copolymer of an α-olefin having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene, 4-methyl-pentene, for example, an ethylene-propylene copolymer (EPR). ), Ethylene-propylene-diene copolymer (EPDM) and the like. The olefin-based elastomer includes dicyclopentadiene, 1,4-hexadiene, cyclooctanediene, methylene norbornene, ethylidene norbornene, butadiene, isoprene, and the like. Examples include coalesced and epoxidized polybutadiene. Examples of the olefin-based elastomer include carboxy-modified NBR obtained by copolymerizing butadiene-acrylonitrile copolymer with methacrylic acid. Further, as the olefin elastomer, ethylene-α-olefin copolymer rubber, ethylene-α-olefin-nonconjugated diene copolymer rubber, propylene-α-olefin copolymer rubber, butene-α-olefin copolymer Rubber etc. are mentioned.

  Specific examples of olefin-based elastomers include milastoma (manufactured by Mitsui Petrochemical), EXACT (manufactured by Exxon Chemical), ENGAGE (manufactured by Dow Chemical), hydrogenated styrene-butadiene rubber “DYNABON HSBR” (manufactured by Nippon Synthetic Rubber) ), Butadiene-acrylonitrile copolymer “NBR series” (manufactured by Nippon Synthetic Rubber Co., Ltd.), “XER series” of both terminal carboxyl group-modified butadiene-acrylonitrile copolymers having a crosslinking point (manufactured by Nippon Synthetic Rubber Co., Ltd.), polybutadiene A partially epoxidized epoxidized polybudadiene “BF-1000 (manufactured by Nippon Soda Co., Ltd.)” and the like can be mentioned.

  Urethane elastomers are composed of structural units of a hard segment composed of low molecular (short chain) diol and diisocyanate and a soft segment composed of high molecular (long chain) diol and diisocyanate. Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene-1,4-butylene adipate), polycaprolactone, and poly (1,6-hexene). Xylene carbonate), poly (1,6-hexylene-neopentylene adipate) and the like. The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000. Examples of the low molecular (short chain) diol include ethylene glycol, propylene glycol, 1,4-butanediol, and bisphenol A. The number average molecular weight of the short-chain diol is preferably 48 to 500. Specific examples of the urethane elastomer include PANDEX T-2185, T-2983N (manufactured by Dainippon Ink & Chemicals, Inc.), sylactolan E790, and the like.

  The polyester elastomer is obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof. Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of these aromatic rings are substituted with a methyl group, an ethyl group, a phenyl group, and the like, Examples thereof include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid and dodecanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These compounds can be used alone or in combination of two or more. Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol; Examples include alicyclic diol, bisphenol A, bis- (4-hydroxyphenyl) -methane, bis- (4-hydroxy-3-methylphenyl) -propane, resorcin and the like. These compounds can be used alone or in combination of two or more. In addition, a multiblock copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component can be used. Polyester elastomers are available in various grades depending on the types and ratios of hard segments and soft segments, and differences in molecular weight. Specific examples of polyester elastomers include Hytrel (Du Pont-Toray), Perprene (Toyobo), Espel (Hitachi Chemical Industries), and the like.

  Polyamide elastomers are composed of hard segments made of polyamide and soft segments made of polyether or polyester, and are roughly divided into two types: polyether block amide type and polyether ester block amide type. The Examples of the polyamide include polyamide 6, polyamide 11, and polyamide 12. Examples of the polyether include polyoxyethylene, polyoxypropylene, polytetramethylene glycol and the like. Specific examples of polyamide-based elastomers include UBE polyamide elastomer (manufactured by Ube Industries), Daiamide (manufactured by Daicel Huls), PEBAX (manufactured by Toray Industries, Inc.), Grilon ELY (manufactured by MS Japan), Novamid (manufactured by Mitsubishi Chemical Corporation). ), Glase (Dainippon Ink Chemical Co., Ltd.) and the like.

  Acrylic elastomers are acrylic esters such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, monomers having an epoxy group such as glycidyl methacrylate, allyl glycidyl ether, and / or vinyls such as acrylonitrile and ethylene. It is obtained by copolymerizing with a monomer. Examples of the acrylic elastomer include acrylonitrile-butyl acrylate copolymer, acrylonitrile-butyl acrylate-ethyl acrylate copolymer, acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, and the like.

  Silicone elastomers are mainly composed of organopolysiloxane, and are classified into polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. Further, a part of organopolysiloxane modified with a vinyl group, an alkoxy group or the like may be used. Specific examples of the silicone elastomer include KE series (manufactured by Shin-Etsu Chemical Co., Ltd.), SE series, CY series, SH series (above, manufactured by Toray Dow Corning Silicone Co., Ltd.) and the like.

  In addition to the above-mentioned elastomer, a rubber-modified epoxy resin can be used. The rubber-modified epoxy resin is, for example, a part or all of the epoxy groups such as the above-mentioned bisphenol F type epoxy resin, bisphenol A type epoxy resin, salicylaldehyde type epoxy resin, phenol novolac type epoxy resin, or cresol novolak type epoxy resin. Is obtained by modification with carboxylic acid-modified butadiene-acrylonitrile rubber, terminal amino-modified silicone rubber or the like.

  As the (F) elastomer used in the photosensitive resin composition of the present invention, from the viewpoint of shear adhesion and thermal shock resistance, both terminal carboxyl group-modified butadiene-acrylonitrile copolymers and polyester-based elastomer Esper ( Espel 1612, 1620, manufactured by Hitachi Chemical Co., Ltd.) and epoxidized polybutadiene are preferred.

  When the (F) elastomer is contained in the photosensitive resin composition, the content is preferably 5 to 30 parts by mass with respect to 100 parts by mass of the total solid content of the component (A) and the component (E). 10 to 25 parts by mass is more preferable, and 15 to 20 parts by mass is particularly preferable. When this content is within the above range, it is possible to further improve the shear adhesion and thermal shock resistance.

  The photosensitive resin composition of the present invention preferably further contains (G) a phenoxy resin. (G) By including a phenoxy resin, not only can the adhesiveness with the conductor layer of the printed wiring board be used when the photosensitive resin composition is used for the solder resist, but also the flexibility of the cured film. And heat resistance can be improved.

  (G) As a phenoxy resin, the phenoxy resin which has a repeating unit represented by following General formula (5) can be used, for example.

In the formula, R ¹¹ represents a hydrogen atom or a methyl group, and m represents an integer of 30 or more. Phenoxy resins are those wherein R ¹¹ is hydrogen atom, any of those R ¹¹ structural units and R ¹¹ as or R ¹¹ is a methyl group is a hydrogen atom is present both a structural unit which is methyl There may be.

In the above general formula (5), examples of the phenoxy resin in which R ¹¹ is a methyl group include YP-50, YP-50S, YP-55 (manufactured by Tohto Kasei Co., Ltd.), Epicoat 1256 (manufactured by Japan Epoxy Resin Co., Ltd.). ), PKHC, PKHH, PKHB (above, manufactured by InChem Corp.) and the like. These are used singly or in combination of two or more.

Examples of the phenoxy resin having both a structural unit in which R ¹¹ is a hydrogen atom and a structural unit in which R ¹¹ is a methyl group include YP-70, FX239 (above, manufactured by Tohto Kasei Co., Ltd.), Epicoat 4250, Epicoat 4275 (manufactured by Japan Epoxy Resin Co., Ltd.) and the like. These are used singly or in combination of two or more.

  The weight average molecular weight of these (G) phenoxy resins is preferably 20,000 to 100,000, and more preferably 30,000 to 80,000. When the weight average molecular weight is less than 20,000, the flexibility of the obtained cured film tends to be lowered, and when it exceeds 100,000, the developability tends to be lowered. In the present invention, the weight average molecular weight is a value measured by gel permeation chromatography (GPC) and converted by a calibration curve using standard polystyrene.

When (G) phenoxy resin is contained in the photosensitive resin composition, the content thereof is 5 to 30 parts by mass with respect to 100 parts by mass of the total solid content of the component (A) and the component (E). Preferably, it is 10-25 mass parts, More preferably, it is 15-20 mass parts. When this content is within the above range, it is possible to further improve the shear adhesion and heat resistance.
.

  The photosensitive resin composition of the present invention preferably further contains (H) blocked isocyanate. (H) By containing block isocyanate, the sclerosis | hardenability of the photosensitive resin composition and the heat resistance of the cured film obtained can be improved more.

  (H) As the blocked isocyanate, an addition reaction product of a polyisocyanate compound and an isocyanate blocking agent is used. Examples of the polyisocyanate compound include tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, naphthylene diisocyanate, bis (isocyanate methyl) cyclohexane, tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, and isophorone diisocyanate. Polyisocyanate compounds, and adducts, burettes and isocyanurates of these.

  Examples of the isocyanate blocking agent include phenolic blocking agents such as phenol, cresol, xylenol, chlorophenol and ethylphenol; lactam blocking agents such as ε-caprolactam, δ-palerolactam, γ-butyrolactam and β-propiolactam; Active methylene blocking agents such as ethyl acetoacetate and acetylacetone; methanol, ethanol, propanol, butanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl Ether, methyl glycolate, butyl glycolate, diacetone alcohol, lactic acid And alcohol-based blocking agents such as ethyl lactate; oxime-based blocking agents such as formaldehyde oxime, acetaldoxime, acetoxime, methyl ethyl ketoxime, diacetyl monooxime, cyclohexane oxime; butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, thiophenol, Mercaptan block agents such as methylthiophenol and ethylthiophenol; Acid amide block agents such as acetic acid amide and benzamide; Imide block agents such as succinimide and maleic imide; Amines such as xylidine, aniline, butylamine and dibutylamine Blocking agents; imidazole blocking agents such as imidazole and 2-ethylimidazole; imine blocking agents such as methyleneimine and propyleneimine It is.

  The block isocyanate which consists of said polyisocyanate and blocking agent is used individually by 1 type or in combination of 2 or more types.

  When (H) block isocyanate is contained in the photosensitive resin composition, the content thereof is 1 to 20 parts by mass with respect to 100 parts by mass of the total solid content of the component (A) and the component (E). Preferably, it is 3-15 mass parts, More preferably, it is 5-10 mass parts. When this content is within the above range, the heat resistance can be further improved.

  In the photosensitive resin composition of the present invention, if necessary, known colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, kustal violet, titanium oxide, carbon black, naphthalene black, hydroquinone, Polymerization inhibitors such as methyl hydroquinone, hydroquinone monomethyl ether, catechol and pyrogallol, thickeners such as benton and montmorillonite, silicone, fluorine and vinyl resin antifoaming agents, silane coupling agents, and antimony trioxide Various known additives such as a flammable auxiliary agent can be used.

  Moreover, the thermosetting accelerator can be used for the photosensitive resin composition of this invention as needed. Examples of thermosetting accelerators include boron trifluoride-amine complex, dicyandiamide, organic acid hydrazide, diaminomaleonitrile, diaminodiphenylmethane, metaphenylenediamine, diaminodiphenylmethane, metaxylenediamine, diaminodiphenylsulfone, and “Hardener HT972” (Ciba Specialty).・ Aromatic amines such as Chemicals; phthalic anhydride, trimellitic anhydride, ethylene glycol bis (anhydrotrimellitate), glycerol tris (anhydrotrimellitate), benzophenone tetracarboxylic anhydride, etc. Aromatic acid anhydride; aliphatic acid anhydride such as maleic anhydride and tetrahydrophthalic anhydride; metal salt of acetylacetone such as zinc acetylacetonate; enamine, tin octylate, quaternary Tertiary phosphine such as phosphonium salt and triphenylphosphine; Phosphonium salt such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosphonium chloride; benzyltrimethylammonium chloride and phenyltributylammonium chloride Quaternary ammonium salts such as diphenyliodonium tetrafluoroporate; antimonates such as triphenylsulfonium hexafluoroantimonate; dimethylbenzylamine, 1,8-diazabicyclo [5,4,0] undecene, m -Tertiary amines such as aminophenol, 2,4,6-tris (dimethylaminophenol), tetramethylguanidine; 2-ethyl-4-methylimidazole , 2-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl imidazole, and 2-phenyl-4-methyl-5-hydroxymethyl imidazole imidazoles. These are used singly or in combination of two or more. Moreover, when these thermosetting accelerators are contained in the photosensitive resin composition, the content thereof is preferably 0.01 to 10% by mass based on the total solid content of the photosensitive resin composition.

  The photosensitive resin composition of the present invention can be obtained by uniformly kneading and mixing each of the above-described blending components with a roll mill, a bead mill or the like. According to such a photosensitive resin composition, by having the above-described configuration, exposure tolerance, development tolerance, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, flexible It is possible to form a high-performance cured film that satisfies all properties and mechanical properties at a high level. Moreover, the cured film obtained is excellent also in a flame retardance, a mechanical characteristic, and electrical insulation. Therefore, the said photosensitive resin composition can be used suitably for manufacture of a printed wiring board etc.

(Resist pattern forming method and printed wiring board manufacturing method)
The method for forming a resist pattern of the present invention comprises laminating a photosensitive resin composition layer comprising the above photosensitive resin composition of the present invention on a substrate, and irradiating the photosensitive resin composition layer with actinic rays in an image form. In this method, the exposed portion is photocured, and then the unexposed portion is removed by development. Here, a flexible printed wiring board etc. are mentioned as a board | substrate.

  Lamination of the photosensitive resin composition layer on the substrate is, for example, 10 to 200 μm of the photosensitive resin composition by a method such as a screen printing method, a spray method, a roll coating method, a curtain coating method, or an electrostatic coating method. It can apply by apply | coating on a board | substrate with a film thickness, and drying a coating film at 60-110 degreeC.

Moreover, the photosensitive resin composition on a board | substrate using the photosensitive element provided with a support body and the photosensitive resin composition layer which consists of the photosensitive resin composition of the said this invention formed on this support body. You may laminate | stack a physical layer. As a lamination method in that case, when the photosensitive element is provided with a protective film, the protective film is removed, and then the photosensitive resin composition layer is heated to about 70 ° C. to 130 ° C. while being applied to the substrate at 0.1 MPa to 1 MPa. the degree method in which bonding at a pressure of ^{(1kgf / cm 2 ~10kgf / cm} 2 or so) can be mentioned. Such a lamination process may be performed under reduced pressure. The surface of the substrate on which the photosensitive resin composition layer is laminated is usually a metal surface, but is not particularly limited.

  The exposed portion is photocured by irradiating the photosensitive resin composition layer laminated on the substrate in this way with an actinic ray in an image form through a negative or positive mask pattern. At this time, when the photosensitive resin composition layer is laminated using the photosensitive element, a support is present on the photosensitive resin composition layer, but the support is transparent to the actinic ray. In some cases, actinic rays can be irradiated through the support, and when the support is light-shielding against actinic rays, the photosensitive resin composition layer is irradiated with actinic rays after the support is removed. To do.

  As the active light source, a conventionally known light source, for example, a light source that effectively emits ultraviolet light, visible light, or the like, such as a carbon arc lamp, a mercury vapor arc lamp, a high-pressure mercury lamp, or a xenon lamp is used. Further, a laser direct drawing exposure method or the like can also be used.

  After formation of the exposed portion, the photosensitive resin composition layer (unexposed portion) other than the exposed portion is removed by development to form a resist pattern. As a method for removing such an unexposed portion, when a support is present on the photosensitive resin composition layer, the support is removed with an auto peeler or the like, and a developer such as an alkaline aqueous solution, an aqueous developer, or an organic solvent is used. Examples include a method in which an unexposed portion is removed and developed by wet development or dry development. Examples of the alkaline aqueous solution used for wet development include a dilute solution of 0.1% by mass to 5% by mass of sodium carbonate, a dilute solution of 0.1-5% by mass of potassium carbonate, and 0.1% by mass to 5% by mass of hydroxide. Examples include a dilute solution of sodium. The pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted according to the developability of the photosensitive resin composition layer. Moreover, you may mix surfactant, an antifoamer, an organic solvent, etc. in alkaline aqueous solution. Examples of the development method include a dip method, a spray method, brushing, and slapping.

Next, as a treatment after development, the exposed portion is sufficiently cured by post-exposure (ultraviolet light exposure) and / or post-heating to obtain a cured film. The post-exposure is preferably performed with an exposure amount of 1 to 5 J / cm ² . Post-heating is preferably performed at 100 to 200 ° C. for 30 minutes to 12 hours.

  The manufacturing method of the printed wiring board of this invention is a method including the process of forming a permanent mask on a board | substrate with the formation method of the resist pattern of the said invention. The permanent mask thus formed is excellent in exposure latitude, development latitude, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, flexibility, and mechanical properties. Therefore, this permanent mask effectively functions as a solder resist, an interlayer insulating film or the like in the printed wiring board.

EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on a reference example, an Example, and a comparative example, this invention is not limited to a following example.

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis A type)]
In a flask equipped with a stirrer, reflux condenser and thermometer, (a) component bisphenol A type epoxy resin (in general formula (1), R ¹ is all glycidyl group and R ² is all methyl group , Epoxy equivalent: 185, manufactured by Nippon Kayaku Co., Ltd., trade name: RE-310S) 1650 parts by mass, (b) 740 parts by mass of acrylic acid, 1 part by mass of methylhydroquinone, 850 parts by mass of carbitol acetate, and solvent 100 parts by mass of naphtha was charged and heated and stirred at 70 ° C. to dissolve the mixture. Next, the obtained solution is cooled to 50 ° C., 2 parts by mass of triphenylphosphine and 75 parts by mass of solvent naphtha are added thereto and heated to 100 ° C., and the solid content acid value becomes 1 mgKOH / g or less. Reacted until. Next, the obtained solution is cooled to 50 ° C., and 650 parts by mass of tetrahydrophthalic anhydride, 75 parts by mass of carbitol acetate, and 75 parts by mass of solvent naphtha are added thereto as component (c). Reacted for hours. Thereby, an acid-modified vinyl group-containing epoxy resin (bis A type) having a solid content acid value of 80 mgKOH / g and a solid content of 62% by mass was obtained as the component (A).

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis-F type)]
As the component (a), an epoxy resin in which R ¹ is a glycidyl group and R ² is a hydrogen atom in the general formula (1), epoxy equivalent: 180, manufactured by Japan Epoxy Resin Co., Ltd., trade name: 806) was used. In the same manner as in the synthesis example of the acid-modified vinyl group-containing epoxy resin (bis A type), the acid-modified vinyl group-containing epoxy having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass as the component (A) A resin (bis F type) was obtained.

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis A type F type copolymer)]
As component (a), in general formula (1), R ¹ is all glycidyl group, R ² is hydrogen atom and methyl group (however, R ² bonded to the same carbon atom is the same, hydrogen atom and methyl group The epoxy resin (epoxy equivalent: 190, manufactured by Japan Epoxy Resin Co., Ltd., trade name: 828EL) was used except that the molar ratio was 1: 3). In the same manner as in Example, an acid-modified vinyl group-containing epoxy resin (bis A type F type copolymer) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass was obtained as the component (A).

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis A type novolak)]
(A) Synthesis example of an acid-modified vinyl group-containing epoxy resin (bis A type) except that an epoxy resin (epoxy equivalent: 205) in which R ⁵ is all methyl groups in general formula (3) is used as component (a) In the same manner as above, an acid-modified vinyl group-containing epoxy resin (bis A type novolak) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass was obtained as the component (A).

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis F type novolak)]
(A) Synthesis example of an acid-modified vinyl group-containing epoxy resin (bis A type) except that an epoxy resin (epoxy equivalent: 200) in which R ⁵ is all hydrogen atoms in general formula (3) is used as component (a) In the same manner as above, an acid-modified vinyl group-containing epoxy resin (bis F type novolak) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass was obtained as the component (A).

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis A type F phenol novolak)]
(A) Acid-modified vinyl group-containing epoxy except that an epoxy resin (epoxy equivalent: 200) in which R ³ is all glycidyl groups and R ⁴ is all methyl groups in general formula (2) is used as component (a) In the same manner as in the synthesis example of the resin (bis A type), an acid-modified vinyl group-containing epoxy resin (bis A type F phenol novolak) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass as the component (A) Got.

[Synthesis example of acid-modified vinyl group-containing epoxy resin (bis F type F phenol novolak)]
(A) An acid-modified vinyl group-containing epoxy, except that an epoxy resin (epoxy equivalent: 185) in which R ³ is all glycidyl groups and R ⁴ is all hydrogen atoms in general formula (2) is used as component (a) In the same manner as in the synthesis example of the resin (bis A type), an acid-modified vinyl group-containing epoxy resin (bis F type F phenol novolac) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass as the component (A) Got.

[Synthesis example of acid-modified vinyl group-containing epoxy resin (cresol novolac type)]
Synthesis Example of Acid-Modified Vinyl Group-Containing Epoxy Resin (Bis A Type) Except for the use of an epoxy resin (epoxy equivalent: 210) in which R ⁶ is all methyl groups in general formula (4) as component (a) In the same manner as above, an acid-modified vinyl group-containing epoxy resin (cresol novolak type) having a solid content acid value of 90 mgKOH / g and a solid content of 65% by mass was obtained as the component (A).

[Synthesis of acrylic resin A]
In a flask equipped with a stirrer, reflux condenser, thermometer, dropping funnel and nitrogen gas introduction tube, 500 g of a mixed solution of methyl cellosolve and toluene mixed at a mass ratio of 3: 2 is added, and stirred while blowing nitrogen gas. And heated to 85 ° C. On the other hand, a solution (hereinafter referred to as “solution a”) in which 150 g of methacrylic acid, 300 g of methyl methacrylate and 150 g of styrene and 2.5 g of azobisisobutyronitrile were mixed as a comonomer was prepared. This solution a was added dropwise to the above mixture heated to 85 ° C. in the flask over 4 hours, and then kept warm at 85 ° C. with stirring for 2 hours. Further, a solution (hereinafter referred to as “solution b”) in which 0.5 g of azobisisobutyronitrile was dissolved in 100 g of a mixed solution in which methyl cellosolve and toluene were mixed at a mass ratio of 3: 2 was added to the flask over 10 minutes. It was dripped. The solution in the flask after completion of dropping was kept at 85 ° C. for 5 hours while stirring, and then cooled to obtain an acrylic resin A solution. The nonvolatile content (solid content) of the solution of the acrylic resin A was 50% by mass, and the weight average molecular weight of the acrylic resin A was 20000. The weight average molecular weight was measured by a gel permeation chromatography method and was derived by conversion using a standard polystyrene calibration curve. The conditions of GPC are as follows.

(GPC conditions)
Pump: Hitachi L-6000 type [manufactured by Hitachi, Ltd.]
Column: Gelpack GL-R420 + Gelpack GL-R430 + Gelpack GL-R440 (3 in total) (above, manufactured by Hitachi Chemical Co., Ltd., trade name)
Eluent: Tetrahydrofuran Measurement temperature: 40 ° C
Flow rate: 1.75 mL / min Detector: Hitachi L-3300 type RI [manufactured by Hitachi, Ltd.]

[Synthesis of acrylic resins B to E]
In the synthesis of the acrylic resin A, the weight average molecular weight of the resulting acrylic resin is adjusted by changing the amount of azobisisobutyronitrile added when preparing the solution a. Otherwise, the acrylic resin A is synthesized. In the same manner, solutions of acrylic resins B to E were obtained. The solutions of acrylic resins B to E were prepared by dissolving methyl cellosolve and toluene in a mixed solution in a mass ratio of 3: 2 so that the nonvolatile content (solid content) was 50% by mass. The weight average molecular weights and acid values of the resulting acrylic resins B to E are shown in Table 1 below.

(Reference Examples 1-3, 8-12, Examples 4-7 and Comparative Examples 1-4)
According to the composition (unit: part by mass) shown in the following Tables 2 to 4, the compositions A and B were separately blended and prepared by kneading with a three-roll mill. Next, 70 parts by mass of composition A and 30 parts by mass of composition B were mixed to obtain a photosensitive resin composition (resist ink composition). In addition, each compounding quantity of the acid-modified vinyl group containing epoxy resin and acrylic resin AE in the following Tables 2-4 shows the compounding quantity of solid content.

* 1: Irgacure 907 (trade name, manufactured by Ciba-Geigy)
* 2: Kayacure DETX-S (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd.),
* 3: C11-A (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd.)
* 4: Kayalad DPHA (trade name, manufactured by Nippon Kayaku Co., Ltd.)
* 5: ESLV-120TE (trade name, 1,3,5-triglycidyl isocyanate, manufactured by Nippon Steel Chemical Co., Ltd.).

(Production of evaluation board)
The photosensitive resin compositions of Reference Examples 1 to 3 , 8 to 12 , Examples 4 to 7 and Comparative Examples 1 to 4 were screen-printed using a 120-mesh Tetron screen, and the thickness after drying was about 30 μm. It applied to a copper clad laminated board so that it might become, It was made to dry for 30 minutes at 80 degreeC with a hot air circulation type dryer. This obtained the evaluation board | substrate with which the photosensitive resin composition layer which consists of a photosensitive resin composition was laminated | stacked on the copper clad laminated board.

  Each characteristic was evaluated by the method shown below using the obtained evaluation substrate. The obtained results are collectively shown in Tables 5 to 10.

(Developability)
A mask with a via mask opening size of 100 μm is placed on the photosensitive resin composition layer of the evaluation substrate, irradiated with ultraviolet rays with an integrated exposure amount of 300 mJ / cm ² using an ultraviolet exposure device, and then 60% with 1% aqueous sodium carbonate solution. Spray development was performed at a pressure of 0.18 MPa for 2 seconds. Thereafter, the evaluation substrate was visually observed to confirm the presence or absence of the development residue, and evaluated according to the following criteria. Note that the undeveloped residue is a resist residue that remains on the substrate because the resist in the unexposed area to be removed is not sufficiently removed. If there is an undeveloped residue, a desired wiring pattern may not be formed in the subsequent copper etching step, which is not preferable.
○: No development residue
X: Development remaining.

(Exposure margin)
A mask with a via mask opening size of 100 μm is placed on the photosensitive resin composition layer of the evaluation substrate, and ultraviolet rays are used under each condition of accumulated exposure amounts of 50, 100, 150, 200, 250, and 300 mJ / cm ² using an ultraviolet exposure device. 6 evaluation substrates irradiated with the above were prepared. Thereafter, each of the evaluation substrates was spray-developed with a 1% aqueous sodium carbonate solution for 60 seconds at a pressure of 0.18 MPa, and the exposure margin was evaluated by visually observing whether the following reference via opening was obtained. Evaluated.
A: A via opening of 90 μm or more and 100 μm or less was obtained,
Δ: A via opening of 50 μm or more and less than 90 μm was obtained,
X: A via opening of less than 50 μm was obtained.

(Development margin)
A mask having a via mask opening size of 100 μm was placed on the photosensitive resin composition layer of the evaluation substrate, and six evaluation substrates were prepared by irradiating ultraviolet rays with an integrated exposure amount of 300 mJ / cm ² using an ultraviolet exposure device. Thereafter, spray development was performed with a 1% sodium carbonate aqueous solution at a pressure of 0.18 MPa under conditions of 30, 40, 50, 60, 80, and 120 seconds, respectively, to obtain the following standard via opening. The development latitude was evaluated by visually observing whether or not it was observed.
A: A via opening of 90 μm or more and 100 μm or less was obtained,
Δ: A via opening of 50 μm or more and less than 90 μm was obtained,
X: A via opening of less than 50 μm was obtained.

(Via shape)
A mask with a via mask opening size of 100 μm is placed on the photosensitive resin composition layer of the evaluation substrate, irradiated with ultraviolet rays with an integrated exposure amount of 300 mJ / cm ² using an ultraviolet exposure device, and then 60% with 1% aqueous sodium carbonate solution. Spray development was performed at a pressure of 0.18 MPa for 2 seconds. Thereafter, the shape of the obtained via was visually observed and evaluated according to the following criteria.
○: The via shape of 90/100 or more was a tapered shape,
Δ: The via shape of 50/100 or more and less than 90/100 was a tapered shape,
X: The via shape has a taper shape of less than 50/100.

(Adhesion)
The photosensitive resin composition layer of the evaluation substrate is irradiated with ultraviolet rays having an integrated exposure amount of 300 mJ / cm ² using an ultraviolet exposure device, and then spray development is performed with a 1% sodium carbonate aqueous solution for 60 seconds at a pressure of 0.18 MPa. went. Using this evaluation substrate, a peel test was performed by a method according to JIS K5400. That is, 100 1 mm grids were prepared on the photosensitive resin composition layer of the evaluation substrate, and a cellophane tape was applied to the grids and then peeled off. The peeled state after the peeling was observed, and the adhesion was evaluated according to the following criteria.
○: 90/100 or more of the grid is not peeled,
(Triangle | delta): 50/100 or more and less than 90/100 of a grid are no peeling,
X: Less than 50/100 of the grid is not peeled.

(Preparation of test plate)
A negative mask having a predetermined pattern was brought into close contact with the photosensitive resin composition layer of the evaluation substrate, and irradiated with 300 mJ / cm ² of ultraviolet rays using an ultraviolet exposure device. Thereafter, spray development was performed with a 1% aqueous sodium carbonate solution for 60 seconds at a pressure of 0.18 MPa, and the unexposed area was dissolved and developed. Next, heating was performed at 150 ° C. for 1 hour to obtain a test plate having a cured film of the photosensitive resin composition layer. The following characteristics were evaluated using this test plate.

(Solder heat resistance)
After applying the rosin flux to the cured film of the test plate, it was immersed in a solder bath at 260 ° C. for 10 seconds. After repeating this for 6 cycles, the appearance of the cured film was visually observed, and the solder heat resistance was evaluated according to the following criteria.
○: There is no abnormality (peeling, swelling) in the appearance of the cured film, and there is no solder peeling.
X: Abnormality (peeling, blistering) in the appearance of the cured film, or solder peeling.

(Electric corrosion resistance)
After leaving the test plate at 85 ° C., 85% RH, 100 V for 1000 hours, the insulation resistance value of the cured film was measured, and the resistance change rate with respect to the insulation resistance value of the cured film before standing (initial) was expressed by the following formula:
Resistance change rate (%) = {(Insulation resistance value after leaving-Insulation resistance value before leaving) / Insulation resistance value before leaving} × 100
The corrosion resistance was evaluated according to the following criteria.
○: Resistance change rate is 10% or less,
X: Resistance change rate exceeds 10%.

(Heat shock resistance)
The process of leaving the test plate at −55 ° C. for 30 minutes and then leaving it at 125 ° C. for 30 minutes is taken as one cycle. After 1000 cycles of this, the cured film is observed visually and under a microscope, and heat resistant according to the following criteria. The impact property was evaluated.
○: No cracking occurred
X: Cracks are generated.

(PCT resistance)
The test plate was allowed to stand for 288 hours under saturated steam at 121 ° C. and 2 atm (PCT treatment). A peel test similar to the adhesion test was performed using the test plate after the PCT treatment, and the adhesion (PCT resistance) of the cured film after the PCT treatment was evaluated according to the same criteria as the adhesion test.

(Elongation rate, tensile strength, elastic modulus)
A test piece of 1 cm wide cured film was prepared from the cured film (thickness 30 μm) of the test plate. About this test piece, elongation rate and tensile strength were measured using a tensile tester (trade name: Autograph AGF-5KN, manufactured by Shimadzu Corporation) at a temperature of 23 ° C., a chuck distance of 20 mm, and a tensile speed of 5 mm / min. The elastic modulus was measured.

  As is apparent from the above results, the photosensitive resin composition of the present invention has exposure latitude, development latitude, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, It was confirmed that a high-performance cured film excellent in flexibility and mechanical properties could be obtained, and that it was suitable for use in forming a solder resist.

  In addition, the resist pattern forming method of the present invention has exposure tolerance, development tolerance, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electric corrosion resistance, flexibility, and mechanical properties. It was confirmed that an excellent high-performance cured film can be obtained and is useful for improving the durability of the solder resist.

  Furthermore, the method for producing a printed wiring board of the present invention includes exposure tolerance, development tolerance, PCT resistance, via shape, heat resistance, developability, adhesion, thermal shock resistance, electrical corrosion resistance, flexibility, mechanical properties. It was confirmed that a high-performance cured film excellent in the above can be obtained and useful for improving the durability of the solder resist.

Claims (6)

(C) (c) Saturated or unsaturated polybasic acid anhydride was further added to the esterified product of (a) an epoxy compound having two or more epoxy groups in one molecule and (b) an unsaturated monocarboxylic acid. An acid-modified vinyl group-containing epoxy resin as an addition reaction product;
(B) a photopolymerization initiator;
(C) a diluent;
(D) a curing agent;
(E) an acrylic resin having a weight average molecular weight of 30,000 to 120,000;
And (a) the epoxy compound is any one or more of compounds represented by the following general formula (2) or (3 ) .

[Wherein, R ³ represents a hydrogen atom or a glycidyl group, R ⁴ represents a hydrogen atom or a methyl group, and n2 represents an integer of 1 or more. A plurality of R ³ and R ⁴ may be the same or different. ]

[Wherein, R ⁵ represents a hydrogen atom or a methyl group, and n3 represents an integer of 1 or more. A plurality of R ⁵ may be the same or different. ]   (F) The photosensitive resin composition of Claim 1 which further contains an elastomer.   (G) The photosensitive resin composition of Claim 1 or 2 which further contains a phenoxy resin.   (H) The photosensitive resin composition as described in any one of Claims 1-3 which further contains block isocyanate.   A photosensitive resin composition layer comprising the photosensitive resin composition according to claim 1 is laminated on a substrate, and the photosensitive resin composition layer is irradiated with actinic rays in an image form. A method for forming a resist pattern, wherein an exposed portion is photocured and then an unexposed portion is removed by development.   A method for manufacturing a printed wiring board, wherein a permanent mask is formed on a substrate by the method for forming a resist pattern according to claim 5.